The invention relates to a golf club head construction. More particularly, the invention is related to a three-piece golf club head construction including a stamped or forged face and neck, a cast body, and a hosel tube adapted to be received in the neck.
The design and manufacture of metal wood golf clubs requires careful attention to club head construction. Among the many factors that must be considered are materials selection, materials treatment, structural integrity, and overall geometrical design. Club heads are typically formed from stainless steel, aluminum, or titanium, and are cast, stamped as by forming sheet metal with pressure, forged, or a combination of any two or more of those processes. The club heads may be formed from multiple pieces that are welded together to form a hollow head, as is often the case of club heads designed with either sole plates or crown plates. The multi-piece constructions facilitate access to the cavity formed within the club head, thereby permitting the attachment of various other components to the head such as internal weights and the club shaft. In addition, due to difficulties in manufacturing one-piece club heads to high dimensional tolerances, the use of multi-piece constructions allows the manufacture of a club head to a tight set of standards.
Various multi-piece club head constructions are known. For example, U.S. Pat. No. 5,518,240 to Igarashi discloses a metal wood club head fabricated from cast sections. The head is fabricated in two half-sections, each formed by a casting technique, with the sections being joined by welding together facing edges of the sections along a parting line.
U.S. Pat. No. 5,232,224 to Zeider discloses a golf club head and method of manufacture. The club head has a sole plate formed integrally with a heel, toe, and back wall, and has open front and upper faces across which a face plate and crown plate, respectively, are welded. The base, face plate, and crown plate are all stamped sheet metal parts. A hosel tube projects upwardly at a desired lie angle from the base through an opening in the crown plate.
Another club head construction is disclosed in U.S. Pat. No. 5,346,217 to Tsuchiya et al. The club head is formed in three pieces including a face section, a crown section, and a sole section. The pieces are united with a separate hosel.
Despite these developments, there exists a need for an improved golf club head construction. In particular, there is a need for a golf club head that can be formed from several components that may be fixed together. More particularly, there is a need for a golf club head with a thin, stamped or forged face with a neck portion that receives a hosel tube for providing enhanced structural integrity to the club head.
The present invention is related to a golf club head adapted for attachment to a shaft. The head includes a first portion forming a face and neck. The neck has a keyed section. The head also includes a second portion forming a body with a crown region and a sole region, the crown region including a keyway. In addition, the head includes a third portion forming a hosel tube that has a top end which is configured and dimensioned for receiving the shaft, as well as a bottom end. The hosel tube is received in the neck and fixed thereto, and the first portion is fixed to the body to form a cavity. The keyed section mates with the keyway. The first portion may be forged or stamped and the second portion may be cast, or both the first and second portions may be cast.
In one embodiment, the sole region includes a hole therein, with the hole being configured and dimensioned to receive the hosel tube. The hosel tube has an upper portion, a lower portion, and a shoulder portion extending therebetween. When fully inserted in the neck of the first portion, the shoulder portion abuts the top surface of the neck. The hosel tube has an upper portion with an outer diameter that is greater than the outer diameter of its lower portion, and may further include a top end and a bottom end, with the bottom end being disposed generally coplanar with the sole region adjacent the hole. The hosel tube has a central axis and the lie angle of the club head is between about 40xc2x0 and about 70xc2x0 with respect to the central axis. The second portion may include more than one piece secured together.
The hosel tube may be coupled directly to both the neck of the first portion and the sole region of the second portion, as by welding. The hosel tube may be provided with a through-bore or a blind bore.
The face of the golf club head has an exterior surface and an interior surface, and the interior surface is provided with a centrally thickened region formed thereon and having a thickness of between about 0.06 inch and 0.18 inch. The regions of the face adjacent the centrally thickened region may also be provided with a thickness of between about 0.06 inch and 0.12 inch.